Field of the Invention
The present invention relates to a hydrogel bead for detecting hydrofluoric acid and a kit comprising the same. More particularly, the present invention relates to a hydrogel bead capable of detecting hydrofluoric acid using an organometallic ligand compound that reversibly changes color depending on the concentration of hydrofluoric acid when coming into contact with hydrofluoric acid, and to a kit for detecting hydrofluoric acid comprising the same.
Description of the Prior Art
Hydrofluoric acid is classified as a weak acid, because it is not easily ionized due to a strong hydrogen bond between fluorine and hydrogen, unlike hydrochloric acid that is classified as a strong acid, or other hydrogen halides such as hydrogen bromide. However, if the concentration of hydrofluoric acid in any material increases, the acidity increases rapidly, and thus the material is classified as a highly toxic material, and emits mist odor with an irritant odor.
Hydrofluoric acid is highly useful in various industrial fields, and is mainly used as an alternative to Flon or a raw material for producing fluorocarbon resin. Because hydrofluoric acid easily melts glass or metals, it is used to process the surface of glass or as an agent for treating the surface of a titanium golf club head, the surface of a pot, or the surface of a semiconductor in semiconductor manufacturing processes. In addition, hydrofluoric acid is used as a catalyst in the production of high-quality gasoline having high octane number, and is also widely used for the synthesis of fluorinated organic compounds.
Although hydrofluoric acid is highly useful in various industrial fields as described above, hydrofluoric acid solution and hydrofluoric acid gas are acute and contagious toxic materials that can be used as chemical warfare. Particularly, these materials have a serious problem in that they are easily absorbed into the human body. Because the size of fluorine ions (F−) is smaller than the size of other halogen ions (Cl−, Br−, I−, etc.), hydrofluoric acid easily penetrates the skin. In addition, halogen ions other than fluorine ions are completely dissociated in an aqueous solution by their bonding with hydrogen ions, hydrofluoric acid is not completely dissociated, and thus when it penetrates the skin, hydrofluoric molecules are mostly absorbed into the skin tissue. The extent to which hydrofluoric acid is dissociated into cations (H+) and anions (F−) varies depending on the concentration thereof, and even non-dissociated hydrofluoric acid molecules can be easily absorbed into the skin, because the size thereof is small.
Dissociated fluorine ions in the body react with calcium ions (Ca2+) or magnesium ions (Mg2+) to form the insoluble compound calcium fluoride (CaF2) or magnesium fluoride (MgF2), and for this reason, the body's electrolyte balance is broken while the calcium ion and magnesium ion concentrations of the electrolyte become lower than the normal concentrations.
Particularly, calcium ions play an important role in signaling in vivo, and when hydrofluoric acid enters the body to extremely reduce the concentration of calcium ions, respiratory muscle becomes hardened, resulting in death by suffocation. In addition, if fluorine ions react with bone, they will damage the bone, and fine powdery particles will be deposited due to the produced calcium fluoride. Meanwhile, if hydrofluoric acid aerosol comes into contact with a plant, it will be absorbed into the tissue of the plant to make the metabolism of the plant difficult, the leaf will turn yellow, and ultimately the plant will wither.
Accordingly, to secure safety in processes in which hydrofluoric acid is used, methods for detecting hydrofluoric acid have been actively studied. For example, Korean Patent Laid-Open Publication No. 2009-0067862 (published on Jun. 25, 2009) discloses an analysis kit that can selectively analyze the concentration of free hydrofluoric acid in a mixture of hydrofluoric acid with other acid or solution. The analysis kit is a disposable kit that detects hydrofluoric acid by spectrophotometrically analyzing a color change that occurs when a hydrofluoric acid component comes into contact with a mixture solution containing an iron solution, a nitric acid medium and an acetylacetone solution.
In addition, Japanese Patent Laid-Open Publication No. 2005-156323 (published on Jun. 16, 2005) discloses a method for detecting hydrofluoric acid, which comprises adding an aqueous solution sample containing hydrofluoric acid to an aqueous solution containing a polynuclear complex composed of zirconium, pyrocatechol violet and a polydentate ligand, and analyzing the resulting color change.
However, the kit for detecting hydrofluoric acid according to the prior art is expensive, and is in a liquid form that is not easy to store and transport and not convenient to carry.